package com.atguigu.commonutils;
import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jws;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import org.springframework.util.StringUtils;
import javax.servlet.http.HttpServletRequest; import java.util.Date;
/**
 * @author  */
public class JwtUtils {
    //常量
    public static final long EXPIRE = 1000 * 60 * 60 * 24;//token过期时间
    public static final String APP_SECRET = "ukc8BDbRigUDaY6pZFfWus2jZWLPHO";//密钥
//    生成token字符串的方法
    public static String getJwtToken(String id, String nickname){
        String JwtToken = Jwts.builder()
//                设计jwt头信息
                .setHeaderParam("typ", "JWT")
                .setHeaderParam("alg", "HS256")
                //设计过期时间
                .setSubject("guli-user")
                .setIssuedAt(new Date())
                .setExpiration(new Date(System.currentTimeMillis() + EXPIRE))

                .claim("id", id)//设置token主体部分，存储用户信息
                .claim("nickname", nickname)

                .signWith(SignatureAlgorithm.HS256, APP_SECRET)
                .compact();
        return JwtToken;     }
    /**
     *	判断token是否存在与有效
     *	@param jwtToken
     *	@return     */
    public static boolean checkToken(String jwtToken) {
        if (StringUtils.isEmpty(jwtToken)) return false;
        try {
            Jwts.parser().setSigningKey(APP_SECRET).parseClaimsJws(jwtToken);
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
        return true;
    }
    /**
     *	判断token是否存在与有效
     *	@param request
     *	@return     */
    public static boolean checkToken(HttpServletRequest request) {
        try {
        String jwtToken = request.getHeader("token");
        if(StringUtils.isEmpty(jwtToken)) return false;
        Jwts.parser().setSigningKey(APP_SECRET).parseClaimsJws(jwtToken);
    } catch (Exception e) {
        e.printStackTrace();
        return false;
    }
        return true;     }
    /**
     *	根据token字符串获取会员id
     *	@param request
     *	@return     */
    public static String getMemberIdByJwtToken(HttpServletRequest request) {
        String jwtToken = request.getHeader("token");
        if(StringUtils.isEmpty(jwtToken)) return "";
        Jws<Claims> claimsJws = Jwts.parser().setSigningKey(APP_SECRET).parseClaimsJws(jwtToken);
        Claims claims = claimsJws.getBody();
        return (String)claims.get("id");
    }
}
